1. Field of the Invention
This invention relates to circuits and methods for transferring information to and from an integrated circuit and particularly relates to a system using DMA operations with a serial interface connected to a codec.
2. Description of Related Art
A serial interface is desirable for connection to a codec (coder/decoder) that require relatively low data transfer rates because serial interfaces require few input/output pins. An ideal application for a serial interface is audio and communications codecs where data transfer rates are often low enough that a single serial interface can transmit data to and from multiple digital-to-analog and analog-to-digital converts (DACs and ADCs). A concern in such interfaces is distinguishing data for one converter from data for another converter which is connected to the same interface. The interface must identify the source and/or destination of digital data and route the data appropriately. Complex circuitry can be required to distinguish and separate data associated with multiple DACs and ADCs connected to the same serial interface. Accordingly, simpler serial interface architectures are desired which can handle multiple DACs and ADCs and properly direct data.